Weight material dispensing and cutting system

ABSTRACT

An apparatus includes a receiving module, a conversion module, first and second rollers, a motor, a forcing member, an implement, and a cutting head. The receiving module receives a desired weight value to correct an imbalance of a wheel/tire assembly. The conversion module converts the desired weight value to a corresponding first amount of a wheel weight material. The first and second rollers engage first and second opposing sides of the wheel weight material. The motor drives the first roller according to the first amount. The forcing member presses the second roller in a first direction that forms an angle with an axis of the first roller. The implement selectively forms a mark on the wheel weight material. The cutting head is selectively actuated to separate the first amount from the wheel weight material.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/683,495 now U.S. Pat. No. 8,505,423), filed on Jan. 7, 2010, whichclaims the benefit of U.S. Provisional Application No. 61/143,284, filedon Jan. 8, 2009. The entire disclosures of the above applications areincorporated herein by reference.

FIELD

The present disclosure relates to weight material, and more particularlyto weight material dispensing and cutting systems and methods ofoperating such systems.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

Rotating assemblies are used in many applications. For example only, inautomotive applications, wheel/tire assemblies are used to couple thevehicle to the ground. As the vehicle moves, wheel/tire assembliesrotate many times. At higher rates of speed, any weight imbalance in thewheel/tire assemblies may result in vibration, which increases wear onvehicle components and may be perceived as a poor ride by the driver.

As a result, wheel/tire assemblies are balanced in a balancing process.A balancing machine may spin a wheel/tire assembly to determine whichpoints of the wheel/tire assembly require more or less weight so thatthe weight will be evenly distributed across the assembly. In mostapplications, it is easier to add additional weight than to removeweight.

The balancing machine may therefore determine how much weight to add towhich locations of the wheel/tire assembly in order to balance theweight distribution of the assembly. In various implementations, twolocations on the assembly may be selected, although more or fewer arepossible. The balancing locations may be predetermined, and thebalancing machine simply determines how much weight to apply to each ofthe predetermined balancing locations.

For a rimmed wheel, lead pound-on weights may be attached to the rim ofthe wheel. For example, lead weights from 0.5 ounces to 10 ounces inincrements of 0.5 ounces may be stocked by businesses that balancewheel/tire assemblies. In this example, 20 different part numbers oflead weights must be inventoried and managed. The various lead weightsmay not look appreciably different in size, thereby leading toinadvertent mixing of the weights and inadvertent use of the wrong sizeof weight. In addition, lead toxicity is a concern. Other materials maybe used for pound-on weights, such as iron. With iron pound-on weights,rust may be a concern.

To address these concerns, systems of encased lead weights have beendeveloped. In these systems, individual weights (such as 0.5 ounceweights) are encased in a non-toxic coating, such as plastic, and thecoating connects the individual weights together to form a segmentedstrip. Depending on the weight desired for balancing, the correspondingnumber of weights can be cut from the strip. The segmented strip ofweights allows a single part number to be inventoried. The segmentedstrip may have an adhesive backing that secures the cut segments to thewheel/tire assembly. The non-toxic coating may protect against leadtoxicity or rust.

SUMMARY

An apparatus includes a receiving module, a conversion module, first andsecond rollers, a stepper motor, a movable carriage, a forcing member, ascribe implement, and a cutting head. The receiving module receives adesired weight value. The conversion module converts the desired weightvalue to a first length of wheel weight material based on a lineardensity of the wheel weight material. The first and second rollersengage first and second opposing sides of a continuous strip of thewheel weight material. The linear density of the wheel weight materialis approximately constant along the continuous strip. The stepper motordirectly drives the first roller based on the first length. The movablecarriage holds the second roller. The forcing member applies pressure tothe movable carriage in a direction toward the first roller. The scribeimplement selectively forms a scribe mark on the wheel weight material.The cutting head is selectively actuated to cut the wheel weightmaterial.

In other features, an apparatus includes a receiving module, aconversion module, first and second rollers, a motor, and a cuttinghead. The receiving module receives a desired weight value. Theconversion module converts the desired weight value to a first length ofwheel weight material based on a linear density of the wheel weightmaterial. The first and second rollers engage first and second opposingsides of a continuous strip of the wheel weight material. The lineardensity of the wheel weight material is approximately constant along thecontinuous strip. The motor directly drives the first roller based onthe first length. The cutting head is selectively actuated to cut thewheel weight material.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples areintended for purposes of illustration only and are not intended to limitthe scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1A is an isometric view of an exemplary continuous weight materialdispensing and cutting system according to the principles of the presentdisclosure;

FIG. 1B is a front view of an exemplary continuous weight materialdispensing and cutting system according to the principles of the presentdisclosure;

FIG. 2A is an isometric view of an exemplary implementation of a cuttingapparatus according to the principles of the present disclosure;

FIG. 2B is a side view of an exemplary implementation of a cuttingapparatus according to the principles of the present disclosure;

FIG. 2C is a top view of an exemplary implementation of a cuttingapparatus according to the principles of the present disclosure;

FIG. 2D is a simplified top view of an exemplary implementation of acutting apparatus according to the principles of the present disclosure;

FIG. 2E is a partial front view of an exemplary implementation of acutting apparatus according to the principles of the present disclosure;

FIGS. 2F-2H are cross-sectional views of exemplary implementations of acutting apparatus along the A-A line of FIG. 2E according to theprinciples of the present disclosure;

FIG. 2I is a composite of end, side, and isometric views of a driveroller depicted in FIG. 2H according to the principles of the presentdisclosure;

FIG. 2J is an end view of an exemplary implementation of a cuttingapparatus according to the principles of the present disclosure;

FIG. 3 is a functional block diagram of an exemplary implementation ofcontrol electronics for the system according to the principles of thepresent disclosure;

FIG. 4A is an isometric view of an exemplary implementation of adispensing apparatus according to the principles of the presentdisclosure;

FIG. 4B is a front view of an exemplary implementation of a dispensingapparatus according to the principles of the present disclosure;

FIG. 4C is a rear view of an exemplary implementation of a dispensingapparatus according to the principles of the present disclosure;

FIG. 4D is a partial rear view of an exemplary implementation of adispensing apparatus according to the principles of the presentdisclosure;

FIG. 5 is an isometric view of an exemplary implementation of a splicingapparatus according to the principles of the present disclosure; and

FIG. 6 is an isometric view of an exemplary implementation of a spoollift according to the principles of the present disclosure.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the disclosure, its application, or uses. For purposesof clarity, the same reference numbers will be used in the drawings toidentify similar elements. As used herein, the phrase at least one of A,B, and C should be construed to mean a logical (A or B or C), using anon-exclusive logical or. It should be understood that steps within amethod may be executed in different order without altering theprinciples of the present disclosure.

As used herein, the term module refers to an Application SpecificIntegrated Circuit (ASIC), an electronic circuit, a processor (shared,dedicated, or group) and memory that execute one or more software orfirmware programs, a combinational logic circuit, and/or other suitablecomponents that provide the described functionality.

When individual lead or iron weights are encased and joined in asegmented strip, the granularity of control of the weight is limited.Cutting a segment with a partial lead weight is not an option because ofthe toxicity of the lead, and cutting the lead may be more difficultthan cutting the casing. Similarly, cutting a segment with a partialiron weight exposes the iron to rust and may be more difficult thancutting only the casing. Weight pieces are therefore only available inincrements of the individual weight. This may limit the accuracy of thebalancing. In addition, if only half a segment in terms of weight isneeded for balancing, the entire segment is used, thereby wasting half asegment.

To overcome the problems of this segmented design, a continuous strip ofhigh-density weight material may be used. For ease of storage, handling,and transportation, the weight material may be flexible. For example,the weight material may be flexible enough to be stored in a roll.Because the weight material is continuous, the granularity of control ofthe weight of a segment can be made arbitrarily small. Manufacturinglimitations may cause the linear density of the continuous weightmaterial to vary slightly over the length of the continuous weightmaterial. The precision of the cutting apparatus and the variance of thelinear density of the weight material therefore determines the weightaccuracy of pieces cut from a continuous strip of the weight material.

In contrast to segmented strips of lead or iron weights connected by acasing, continuous weight material may have a cross-section that issubstantially uniform along the length of the continuous weightmaterial. The segmented material has one cross-section where thelead/iron material is present and a different cross-section in theconnecting spaces where only the casing is present.

Similarly, the linear density of the continuous weight material mayremain approximately constant. This is in contrast to the segmentedmaterial, where the sections including lead/iron have a much higherlinear density than the connecting sections. The continuous weightmaterial may be available in different cross-sectional shapes and sizesto accommodate various aesthetic and packaging concerns.

One side of the continuous weight material may be partially or fullycovered with an adhesive to allow a cut segment to be attached to awheel. The adhesive may be in the form of an acrylic foam tape. A liningor backing may cover an exposed surface of the tape to prevent the tapefrom sticking to the continuous weight material when stored in a roll.In addition, the backing prevents contaminants from reducing theeffectiveness of the adhesive. For example only, the continuous weightmaterial may be available from the 3M Company, such as product numbersTN2015, TN2023, and TN4014.

For purposes of illustration only, the present disclosure describescontinuous weight material in the context of wheel/tire assemblies.However, the systems and methods of the present disclosure apply toother applications where additional precise weights may be needed. Forexample only, precise weights may be used in balancing other componentsin both automotive and non-automotive applications. The components maybe rotating components, such as a flywheel or a driveshaft, or may becomponents that reciprocate or other move in another fashion. Thesystems and methods of the present disclosure apply to weight balancingeven for stationary objects, where desired weight balance parameters maybe specified.

Referring now to FIGS. 1A and 1B, isometric and front views of acontinuous weight material dispensing and cutting system are shown. Astrip 102 of continuous weight material is provided from a dispensingapparatus 104 to a cutting apparatus 106. The dispensing apparatus 104provides the strip 102 from a spool 110. The cutting apparatus 106advances the strip 102 by a specified length, and then cuts the strip102 to create a piece of weight material.

The dispensing apparatus 104 may create a loop 120 from the strip 102 sothat advancing of the strip 102 by the cutting apparatus 106 does nothave to be precisely synchronized with feeding of the strip 102 by thedispensing apparatus 104. In addition, the loop 120 provides a reserveof additional weight material to allow the cutting apparatus 106 tocontinue operating while the spool 110 is being changed. The size of theloop 120 may be limited by a distance to the floor. The size of the loop120 may also be limited by the ability of the cutting apparatus 106 topull the weight of the weight material included in the loop 120. Forexample, motor torque and/or friction may limit the amount of weight thecutting apparatus 106 can pull.

Referring now to FIGS. 2A-2J, various views of an exemplaryimplementation of the cutting apparatus 106 are presented. The cuttingapparatus 106 includes a drive roller 130 that advances a predeterminedlength of the strip 102. A cutting device 140 then cuts the strip 102,thereby creating a piece of weight material. Prior to reaching the driveroller 130, the strip 102 may be drawn through an alignment assembly150. The alignment assembly 150 ensures that the strip 102 enters at thecorrect orientation and position. In various implementations, such as isshown in FIG. 2A, the alignment assembly 150 may include first, second,and third rollers 152, 154, and 156. In various implementations, one ormore of the first, second, and third rollers 152, 154, and 156 may beeliminated.

The height of the first roller 152 may be adjusted based on thecross-sectional thickness of the strip 102. The first roller 152 may beadjusted using an adjustment knob 158. In FIG. 2D, a top viewillustrates that the first roller 152 and the second and third rollers154 and 156 may be adjusted laterally with respect to each other basedon the cross-sectional width of the strip 102. In variousimplementations, the second and third rollers 154 and 156 may be fixed,while the first roller 152 is adjusted laterally.

A first edge 162 of the first roller 152 and a first edge 164 of thesecond roller 154 define the track for the strip 102. The distancebetween the first edges 162 and 164 may therefore be adjusted to beequal to or slightly greater than the cross-sectional width of the strip102. First and second guides 166 and 168 may further prevent the stripfrom moving in a lateral direction. The second guide 168 may be adjustedbased on the cross-sectional width of the strip 102. In variousimplementations, the first and second guides 166 and 168 may beshortened or eliminated altogether.

The drive roller 130 engages the strip 102 and pulls the strip 102underneath the cutting device 140. The drive roller 130 presses thestrip 102 against an idle roller 180. This increases the frictionalforce exerted on the strip 102 by the drive roller 130, thereby reducingslippage. The idle roller 180 may rotate freely, such as on low-frictionbearings, to reduce rubbing that would otherwise occur if the driveroller 130 simply pressed the strip 102 against a fixed surface.

The drive roller 130 may be directly driven by a stepper motor 190.Directly driven means that the axle of the drive roller 130 is integralwith or coupled in line with an output shaft of the stepper motor 190.Directly driven therefore means that the drive roller 130 rotates at thesame angular speed as the stepper motor 190. Directly driven also meansthat an axis around which the drive roller 130 rotates is approximatelycollinear with an axis around which the output shaft of the steppermotor 190 rotates. One advantage of direct driving over other couplingmechanisms, such as gear, belt, or chain drives is that no slop or gearlash develops over time in a direct drive system.

FIGS. 2F-2H depict exemplary configurations for direct driving. Thestepper motor 190 is mounted to a rigid plate 191. An output shaft 192of the stepper motor 190 fits into a corresponding void in a first endof a drive shaft 193. An opposite end of the drive shaft 193 rides in abearing 194. The drive roller 130 is affixed to the drive shaft 193 andtherefore rotates with the drive shaft 193. One or more set screws, suchas set screw 202, may secure the drive roller 130 to the drive shaft193.

One or more set screws 195 may secure the drive shaft 193 to the outputshaft 192. For example only, the output shaft 192 may have across-section as shown in FIG. 2F, which is a circle with two portionsdefined by two chords of the circle removed. Two set screws 195 may bearagainst each flat section 204-1 and 204-2, respectively, of thecross-section.

Referring now to FIG. 2G, the stepper motor 190 is secured to a rigidmotor mount 196. The drive roller 130 is affixed to a drive shaft 197,which is supported by bearings 198. The output shaft 192 is attached toa protruding end of the drive shaft 197 by a coupling 199. The coupling199 may allow for a small amount of axial, lateral, and angularmisalignment between the drive shaft 197 and the output shaft 192.

The misalignment is small and therefore the output shaft 192 and thedrive shaft 197 are still approximately collinear, as required fordirect driving. For example only, an angle misalignment of less than 1degree and a lateral misalignment of less than 7 thousandths of an inchmay still be considered approximately collinear with regard to thedefinition of direct driving. For applications where less precision isrequired, slightly more angular and lateral misalignment may be allowed,such as 5 degrees and 50 thousandths of an inch.

Referring now to FIG. 2H, a unitary version of the drive roller 130 isshown. The drive roller 130 incorporates an axle that is supported bythe bearings 198 and attached to the output shaft 192 of the steppermotor 190 by the coupling 199.

Referring now to FIG. 2I, end, side, and isometric views of the driveroller 130 as shown in FIG. 2H. The drive roller 130 includes a unitarypiece 278 having a roller core 280, axle ends 281 and 282, and bearingends 283 and 284. The axle ends 281 and 282 are on either side of theroller core 280 and may have a smaller diameter than the roller core280. The bearing ends 283 are on either end of the axle ends 281 and282, respectively, and may have a smaller diameter than the axle ends281 and 282.

The unitary piece 278 is formed from a single piece of material. Invarious implementations, the unitary piece 278 is rough machined, suchas by using a lathe, from a piece of round stock, such as 1045 coldrolled steel. The roller core 280 is then coated with a cover material286, which may have a high coefficient of friction and be more compliantthan metal, such as 60-durometer polyurethane. The cover material 286and the bearing ends 283 may then be finely machined, such as by using asurface grinder. In various implementations, the axle ends 281 and 282may also be finely machined.

Referring back to FIG. 2A, the distance the strip 102 is moved with eachstep of the stepper motor 190 depends on configuration of the steppermotor 190 and an electrical driver of the stepper motor 190, as well asthe diameter of the drive roller 130. For example only, the distancemoved with each step may be between 7 and 8 ten thousandths of an inch,or may be four thousandths of an inch. For example only, a systemaccording to the principles of the present disclosure may allow piecesof weight material to be generated with a repeatability of approximately0.5 or 0.25 grams.

The variation in linear density of the weight material, and not theaccuracy of the cutting system, may be the limiting factor with regardto weight repeatability. For example only, a system according to theprinciples of the present disclosure may produce pieces of weightmaterial whose length deviates from the desired length (which may becalculated based on desired weight) by no more than plus or minus 0.5%,for a total range of 1%.

The idle roller 180 is mounted in a carriage 200. The carriage 200 maymove up and down with respect to the strip 102 to accommodate variousthicknesses of the strip 102. In addition, more or less pressure may beapplied by the carriage 200 to increase the frictional force of the idleroller 180. For example, in humid or oily environments, the pressureapplied by the carriage 200 may be increased.

When the idle roller 180 is also driven, a second stepper motor (notshown) may be mounted to the carriage 200 so that the second steppermotor moves up and down with the carriage 200. The second stepper motordirectly drives the idle roller 180 in unison with driving of the driveroller 130 by the stepper motor 190. Alternatively, the idle roller 180may be driven from the stepper motor 190 via a belt/chain or gear train.In another alternative, the stepper motor 190 may directly drive theidle roller 180, and the drive roller 130 is allowed to idle.

Downforce of the carriage 200 may be created in various ways. Forexample, air pressure may be used to press the carriage 200 against thedrive roller 130. In addition, gravity may provide downforce. Further,springs and/or hydraulic pressure may apply downforce to the carriage200. The air pressure or hydraulic pressure may be calibrated using acalibration procedure and/or may be manually set by an operator.

In various implementations, the drive roller 130 and/or the idle roller180 may have a raised pattern that is imprinted on the strip as thestrip passes between the drive roller 130 and the idle roller 180. Thispattern may have aesthetic value. In addition, the raised pattern mayoffer a better grip of the strip 102, reducing slippage.

The stepper motor 190 is electronically controlled to advance apredetermined amount of the strip 102 past the cutting device 140. Oncethis predetermined amount has been fed, the cutting device 140 actuatesa blade 210 to cut a piece off of the strip 102. For example only, thecutting device 140 may be actuated by air pressure.

As shown in more detail with respect to FIG. 2J, the blade 210 may bepositioned so that the cutting edge is not perpendicular to thedirection of travel of the blade 210. This causes the edge of the blade210 to meet the strip 102 at a single point, which maximizes the cuttingforce of the blade 210, similar to an angled guillotine. The blade 210may be a standard trapezoidally shaped utility knife blade. The blademay be secured in a cartridge that is mounted to the cutting device 140without using tools for quick replacement. For example only, thecartridge may be secured by thumbscrews.

A slit 212 may be located beneath the blade 210. The blade 210 cantherefore travel past the bottom of the strip 102, insuring a completecut. The slit 212 may be only slightly wider than the thickness of theblade 210, thereby providing support on either side of the blade 210.This prevents the strip 102 from being pressed through the slit 212 bythe blade 210, especially as the blade 210 dulls.

A shoe 220 may hold down the cut piece of material as the blade 210retracts. The cut piece of weight material then falls free of thecutting apparatus 106. The shoe 220 may not contact a cut piece ofweight material that is very short. In various implementations, atransport system, such as a conveyor, may take the cut piece of weightmaterial from the location of the cutting apparatus 106 to a locationwhere the piece of weight material will be applied.

Locating the cutting apparatus 106 away from the application locationmay be necessary to accommodate space constraints. Alternatively, binsmay be located adjacent to the cutting apparatus 106. For example only,first and second bins 240 and 242 may be provided. The first and secondbins 240 and 242 may correspond to first and second pieces of weightmaterial for a given wheel/tire assembly. Each wheel/tire assembly mayhave two locations for application of wheel weight.

The first piece of weight material will be retrieved from the first bin240 and applied to the first location, while the second piece of weightmaterial will be retrieved from the second bin 242 and applied to thesecond location. A light may be associated with each of the bins 240 and242 and may be illuminated to indicate from which of the bins 240 and242 a piece of weight material should be retrieved.

A first diverter 250 may direct a piece of cut weight material from thecutting apparatus 106 to the first bin 240. A first actuator 252 maymove the diverter 250 to the side, thereby allowing a piece of cut wheelmaterial to fall to a second diverter 254, which then directs the cutweight material to the second bin 242. A second actuator 256 may movethe second diverter 254 to the side. When both the first and seconddiverters 250 and 254 are moved to the side, the cut piece of weightmaterial may fall into a discard bin.

For example, as described in more detail below, when a spliced sectionof the strip 102 is detected, the spliced section may be cut anddiscarded. In addition, pieces used for calibration and pieces at thebeginning or end of a supply of weight material may be discarded. Forexample only, the first and second actuators 252 and 256 may beelectrically powered or may be actuated by air pressure. A suctionsystem may be used to remove the discarded pieces of weight material.The suction system may also dispose of the weight material backing whenit is removed to apply the weight material to the wheel/tire assembly.

In various implementations, the backing material may be removed beforethe cut piece of weight material reaches the first diverter 250. Forexample, the backing material may be removed as the strip 102 passes thedrive roller 130. In such a system, system components that will comeinto contact with the cut piece may be made from or coated with anonstick coating. For example, the first and second diverters 250 and254 and the first and second bins 240 and 242 may be plasma coated orcoated with polytetrafluoroethylene (PTFE) or its equivalents.

The weight material may be applied by human operator or by a robot, withor without human assistance. A robotic application unit may beimplemented in the system. The robotic application unit may retrieve thecut piece of weight material and apply the cut piece of weight materialto an end effector. In various implementations, the robotic applicationunit may hold the piece of weight material with the end effector priorto the material being cut, eliminating the need to pick up the cut pieceof weight material. The end effector may hold the material using anysuitable system, including magnetic, vacuum, and/or mechanical grippingsystems.

The robotic application unit then transports the piece of cut weightmaterial to the wheel/tire assembly, where the end effector presses thepiece of weight material against the appropriate spot on the wheel/tireassembly. In various implementations, a backing material with the weightmaterial is removed by a second gripping apparatus. Alternatively, avacuum may be used to remove the backing. The backing may be disposed ofvia a suction system.

Once the piece of weight material has been applied to the wheel/tireassembly, pressure may be applied across the length of the piece ofweight material to wet-out the piece of weight material. This pressuremay be applied by the end effector or by a second end effector.

In order for an operator to accurately place a piece of weight materialon a given position of a wheel/tire assembly, a witness mark may beadded to the piece of weight material by the cutting apparatus 106. Thewitness mark can then be aligned with a corresponding witness mark onthe wheel.

For example only, a scribe cylinder 260 may be used to scribe a mark onthe side of the strip 102. To accomplish this, the stepper motor 190 mayadvance half of the desired length of the strip 102, at which point thescribe cylinder 260 makes a scribe mark on the strip 102. The steppermotor 190 then advances the remaining portion of the desired length ofthe strip 102. Once the cutting device 140 cuts the piece of weightmaterial from the strip 102, the scribe mark is located in the middle ofthe resulting piece.

The scribe cylinder 260 may actuate a scribe head 262 that creates anindentation on the side of the strip 102. For example only, the scribecylinder 260 may be controlled by air pressure. Sensors may detectwhether the various components of the system are operating correctly.For example only, sensors may measure whether the scribe cylinder 260 isactuating fully and whether the cutting device 140 is actuating fully.

A control enclosure 270 may include electronics that control the steppermotor 190, and when present, the second stepper motor. The stepper motor190 and the second stepper motor may both receive the same electricalsignals to ensure that they operate in unison. The electronics mayinclude one or more processors and circuitry that performs some or allof the functions shown in FIG. 3. The control enclosure 270 may alsoinclude pneumatic and/or hydraulic control devices, such as solenoids.These solenoids may be electrically controlled to provide air and/orhydraulic pressure at various times, such as to actuate the blade 210and the scribe cylinder 260. An air regulator with moisture separatormay assure a clean air supply for pneumatic components.

In various implementations, the control enclosure 270 may includeelectronics that control both the dispensing apparatus 104 and thecutting apparatus 106. The control enclosure 270 may be separate from,or separable from, the remainder of the cutting apparatus 106. One ormore wired or wireless links may allow communication between the controlenclosure 270 and the cutting apparatus 106. In addition, one or morewired or wireless links may allow communication between the controlenclosure 270 and the dispensing apparatus 104. The control enclosure270 may provide one or more power supplies to the cutting apparatus 106and/or the dispensing apparatus 104.

Referring now to FIG. 2J, the blade 210 is secured in a cartridge 214 byset screws 216. The cartridge 214 may slide onto a track of the cuttingdevice 140 and be secured by one or more thumbscrews (not shown).

Referring now to FIG. 3, a functional block diagram of an exemplarycontrol system of the control enclosure 270 is presented. A centralcontrol module 302 may receive weight data from a data receiver module306. The data receiver module 306 may receive desired weight values froma balancing machine. For example only, the data receiver module 306 mayreceive data over a serial interface, a parallel interface, a factorycontrol network, a local area network, or a direct electrical interface.For example only, supported communication protocols may includeEthernet, Datahighway Plus (DH+), controller area network (CAN), andDeviceNet. In various implementations, while the data receiver module306 receives the desired weight values from the balancing machine, thedesired weight values are transferred via another apparatus, such as aconveyor system, an upper-level system, a plant management system, and adata tracking system.

In various implementations, the data receiver module 306 may have aconversion front end (not shown) and a reference interface, such asRS232. The conversion front end converts an incoming interface to thereference interface. In this way, the conversion front end can bereplaced when a new external interface is used, while retaining RS232for internal communication.

The data receiver module 306 may receive two weight values for eachwheel/tire assembly. The central control module 302 provides weightvalues to a length converter module 310, which converts the weightvalues into length values. This conversion is based on the lineardensity of the weight material, a value that may be stored in a lineardensity storage module 314.

The central control module 302 may provide a linear density value to thelinear density storage module 314. Alternatively, the linear densitystorage module 314 may be preprogrammed with values of linear densityfor various available weight materials. The central control module 302may then indicate to the linear density storage module 314 whichmaterial is being used.

In various implementations, the weight to length conversion may beperformed by dividing the desired weight by the linear density of theweight material in use. The central control module 302 may communicatewith an operator input/output device 318. The operator input/outputdevice 318 may provide sensory feedback to an operator and/or mayreceive input from the operator.

For example only, the operator input/output device 318 may allow for theoperator to supply the linear density of the weight material being used.Alternatively, the operator may indicate which weight material is beingused, and the central control module 302 will select the correspondinglinear density in the linear density storage module 314.

In other implementations, the operator input/output device 318 may offerthe operator a selection of linear densities, from which the operatorselects the correct linear density. In various implementations, varioussensors may be present to determine the material's linear density. Forexample only, a calibration scale may be implemented. The centralcontrol module 302 may cause a predetermined length of material to becut. The weight of this length of material, as measured by a calibrationscale, and the requested length can be used to calculate linear density.

Alternatively, the calibration scale may be used to verify accuracy ofthe system. If the linear density as calculated based on the weightmeasured by the calibration scale does not match the expected density,the scale may be out of calibration, the material may be different thanexpected, and/or length errors may be present. This calibration processmay also be manually initiated via the operator input/output device 318.

In various implementations, the central control module 302 may determinelinear density of the weight material based on the cross-sectionalprofile of the weight material. The central control module 302 mayinclude one or more sensors that determine the cross-sectional profileof the weight material. Based on these sensors, the central controlmodule 302 can select or calculate the linear density of the weightmaterial. In various implementations, the volumetric density of theweight material may remain approximately constant. The linear densitycan thereby be calculated from the volumetric density based on thecross-sectional area of the weight material.

Once the central control module 302 has determined a desired length towhich to cut the weight material, the central control module 302provides this length to a stepper actuator control module 322. Thecentral control module 302 may convert the desired length into a numberof steps for the stepper motor 190 and provide the length in units ofsteps.

The stepper actuator control module 322 then controls the stepper motor190 to advance by the requested number of steps. Once the stepperactuator control module 322 has finished its movement, the stepperactuator control module 322 may transmit a completion signal to thecentral control module 302.

The central control module 302 may then request that a cutter actuatorcontrol module 326 actuate the cutting device 140. For example only, thecutter actuator control module 326 may energize a solenoid that allowsair pressure to flow to the cutting device 140, thereby forcing theblade 210 through the weight material.

In various implementations, the central control module 302 may apply ascribe mark to the piece of weight material. Whether the scribe mark isapplied, and to where the scribe mark is applied, may be determined byoperator input from the operator input/output device 318. When a scribemark will be added to the center of the piece, the central controlmodule 302 may provide half the desired length to the stepper actuatorcontrol module 322.

After completion of this half length, the central control module 302provides a signal to the scribe actuator control module 330. The scribeactuator control module 330 then actuates then actuates the scribecylinder 260 to create the scribe mark. The central control module 302then provides the remaining half length to the stepper actuator controlmodule 322.

Once the stepper actuator control module 322 signals that the steppermotor 190 has advanced through the second half of the length, thecentral control module 302 then instructs the cutter actuator controlmodule 326 to cut the weight material. The scribe mark will then be inthe center of the cut piece.

The central control module 302 may provide commands to a diverteractuator control module 334. The diverter actuator control module 334may direct cut pieces between different locations. For example only, thediverter actuator control module 334 may direct a cut piece between oneor more bins and a discard bin. The diverter actuator control module 334may also illuminate a light corresponding to the bin where the cut pieceis located for retrieval by the operator.

The stepper motor 190 drives the drive roller 130, which is mounted inthe carriage 200. The downforce of the carriage 200 against the weightmaterial determines the frictional force, which prevents the weightmaterial from slipping against the drive roller 130. The central controlmodule 302 may modulate the amount of downforce via a carriage downforcecontrol module 338. In various implementations, the carriage downforcecontrol module 338 may control hydraulic and/or air pressure pressingthe carriage 200 against the idle roller 180.

The central control module 302 may receive inputs from one or moresafety sensors 342. For example only, the safety sensors 342 may sensewhether maintenance doors are open. The central control module 302 mayhalt operation of various components, such as the cutter actuatorcontrol module 326 and the scribe actuator control module 330, when anyof the safety sensors 342 indicate that a maintenance door is open.

This prevents the operator from coming in contact with moving parts.Emergency stop switches (not shown) may be located at various locationson both the cutting apparatus 106 and the dispensing apparatus 104. Theemergency stop switches also halt operation of various components. Thisprevents operator injury and equipment damage in event of a fault.

In various implementations, the stepper actuator control module 322 maystill be active when maintenance doors are open. The stepper actuatorcontrol module 322 may control the stepper motor 190 to advance, therebydrawing in new weight material when a new roll is begun. The operatormay signal via the operator input/output device 318 to the centralcontrol module 302 that a new piece of material is being loaded. Thestepper actuator control module 322 may then begin advancing the steppermotor 190 to draw in the new weight material.

A material detection module 346 may detect whether weight material ispresent. For example only, the material detection module 346 may detectonce the roll of weight material has been used up. In this way, thecentral control module 302 can stop operation and not inadvertentlyoutput the last piece, which may be too short due to the weight materialrunning out.

In addition, the central control module 302 will halt actuating thescribe cylinder 260 and the cutting device 140 when no weight materialis present. When loading new material, the material detection module 346may detect that the new weight material is present. The central controlmodule 302 may then direct the stepper actuator control module 322 toadvance the stepper motor 190 to draw the material into the cuttingapparatus 106. The material detection module 346 may use various typesof sensors. For example only, the material detection module 346 mayinterface with a photoelectric sensor, a mechanical sensor, an infraredsensor, and/or an ultrasonic sensor.

A splice detection module 350 may detect splices in the weight material.When one roll of weight material ends, a new roll of weight material canbe spliced to the end of the old roll. In this way, operation iscontinuous, without having to feed a new roll of weight material.However, the splice itself may not be desirable for placing on awheel/tire assembly.

Therefore, when the splice detection module 350 detects a splice, thecentral control module 302 may advance the length of the splice, cut thesplice, and instruct the diverter actuator control module 334 to discardthe material surrounding the splice. After a splice, a predeterminedlength of the new weight material may be cut and weighed to determinethe linear density of the new weight material.

Splices may be created with adhesives that have different materialproperties than the surrounding weight material. For example only, thesplicing material may be adhesive tape. The adhesive tape may have ahigher optical reflectivity than the surrounding weight material. Thischange in optical reflectivity may be sensed by the splice detectionmodule 350 as a splice.

In another example, electrical properties of the adhesive tape, such asmagnetic permeability, may be different than the surrounding weightmaterial. Alternatively, the splicing material may not be detectable byitself; additional material is added to allow for detection. For exampleonly, the splicing tape may be undetectable, so reflective tape isapplied over the splice.

The operator input/output device 318 may allow the operator to repeatthe previous cut. For example, this feature may be used when a piece ofweight material is dropped or misplaced. The operator input/outputdevice 318 may also allow an operator to manually cut a piece of weightmaterial to a given length or having a given weight. This may be usefulwhen integrating with balancing machines that do not output weights in adigital format.

When integrating a system according to the present disclosure with priorart lead balancing stations, a large number of bins may be present, eachhaving a different size of lead weight. The operator input/output device318 may allow the operator to cut a predetermined number of pieces of acertain weight to replace the lead weights in one bin with cut pieces ofthe continuous weight material.

The operator input/output device 318 may allow the user to enter anupper limit and a lower limit, to define a range of weights, as well asan increment. The central control module 302 can then cut apredetermined number of pieces of each increment of weight, from thelower limit to the upper limit. In various implementations, control maypause between each increment, so the cut pieces can be removed from acollection bin and placed in the correct bin previously occupied by thelead weights. The operator can then signal via the operator input/outputdevice 318 to begin cutting the next increment.

In various implementations, the operator input/output device 318 may beseparate from, or separable from, the control enclosure 270. The controlenclosure 270 may be separate from the cutting apparatus 106, thedispensing apparatus 104, and the operator input/output device 318. Thecontrol enclosure 270 may then be placed at any convenient location.Being separate, the operator input/output device 318 may be placed so asto best be accessible to the operator. By separating components,shipping, packaging, service, and replacement may be made easier andmore cost-effective.

Referring now to FIG. 4A-4D, various views of an exemplaryimplementation of the dispensing apparatus 104 are presented. Weightmaterial may be purchased and stored on the spool 110. The spool 110 isloaded into the dispensing apparatus 104 by opening first and seconddoors 408 and 412. The first and second doors 408 and 412 protect theoperator from moving parts and may prevent debris from entering thedispensing apparatus 104.

The spool 110 has first and second ends 414 and 416 whose diameters arelarger than the diameter of a center portion 418 of the spool 110. Thefirst and second ends 414 and 416 ride on first and second axles 420 and422. Each of the axles 420 and 422 may have a flanged roller, whichcorrespond to the first and second ends 414 and 416. The flange of theflanged rollers prevents the spool 110 from moving in an axial directionalong the axles 420 and 422.

In various implementations, a second spool (not shown) may be stored inthe dispensing apparatus 104. The second spool may be located directedabove the spool 110. The second spool may be stored in the dispensingapparatus 104 simply to be located conveniently. However, in variousimplementations, the dispensing apparatus 104 may include machinerythat, once the spool 110 is removed, guides the second spool into theprevious location of the spool 110. In fact, the dispensing apparatus104 may include automated machinery that automatically (or uponactuation of a button or other operator input) replaces the spool 110with the second spool.

As shown in FIGS. 4C-4D, the first and second axles 420 and 422 may becoupled via a chain or a belt. This causes the first and second axles420 and 422 to rotate together. The first and second axles 420 and 422may be driven by a motor 430 via another belt or chain. The motor 430turns the first and second axles 420 and 422 in order to dispense moreweight material from the spool 110.

Weight material from the spool 110 passes through first, second, andthird rollers 440, 442, and 444. The weight material then passes througha splicing apparatus 450, which will be described in more detail below.In various implementations, the splicing apparatus 450 may be located inanother position, such as on the exterior of the dispensing apparatus104. The splicing apparatus 450 may be portable, and may behandheld—when not in use, the splicing apparatus 450 may then betemporarily affixed to the dispensing apparatus 104. The weight materialthen passes over a pulley 460. The pulley 460 is driven by a motor 464.The motor 464 turns the pulley 460 to provide the loop 120 of weightmaterial.

The size of the loop 120 may be determined by operating requirements ofthe system and may be set to provide enough weight material so that asplice can be made while operation continues unabated using materialfrom the loop 120. An idle roller 468 applies pressure to the weightmaterial to keep the weight material from slipping against the pulley460. Downforce is applied to the idle roller 468 by a downforce device470. For example only, the downforce device 470 may include a spring.Alternatively, the downforce device 470 may be fixed in place, creatinga fixed gap between the idle roller 468 and the pulley 460.

The dispensing apparatus 104 may include one or more sensors todetermine the length of the loop 120. For example, as shown in FIGS. 4Aand 4B, the dispensing apparatus 104 may include sensors 474-1, 474-2,and 474-3. If the length of the loop 120 decreases below a predetermineddistance, operation of the cutting apparatus 106 may be halted toprevent the weight material from being pulled taught and slipping in thecutting apparatus 106.

The motor 464 may drive the pulley 460 to establish a predeterminedlength of the loop 120. When splicing is being performed, the motor 464may fix the position of the pulley 460 to keep the strip 102 from movingand allow precise splicing. When splicing, the trailing end of theprevious roll of weight material may be centered in the splicingapparatus 450. The previous spool 110 can be removed and replaced with anew spool 110 containing a new roll of weight material.

The new weight material may be threaded through the rollers 440, 442,and 444 so that the leading end of the new weight material butts upagainst the trailing end of the previous roll of weight material. Thetwo ends are then joined. For example only, a length of adhesive tapemay be present at the splicing apparatus 450. In order to join theleading end of the new weight material to the trailing end of theprevious weight material, the operator may apply the piece of tape tothe ends and apply enough pressure to ensure adhesion.

In addition, splice indicia may be applied to the weight material. Forexample only, reflective tape may be applied to allow for detection ofthe splice. Alternatively, marks, paint, or other indicia may be appliedto the weight material. Once the splice is completed, the motor 464 maydrive the pulley 460 to reestablish the desired length of the loop 120.The dispensing apparatus 104 may be designed to isolate access to thesplicing apparatus 450 from access to the spool 110. In this way, thesplicing apparatus 450 can only be accessed once the spool 110 is loadedand associated safety doors are closed. Then, the splice can beperformed without exposing the operator to the mechanics of the motor430 and the first and second axles 420 and 422.

For example only, during normal operation (when not splicing), the motor464 may drive the pulley 460 such that a bottom of the loop 120 remainsbetween the sensors 474-1 and 474-2. In various implementations, thesensors 474-1, 474-2, and 474-3 may be photoelectric sensors. Thesensors 474-1, 474-2, and 474-3 may be diffuse sensors, which includeboth a light emitter and a detector, eliminating the need for separatelight emitters or detectors on an opposite side of the loop 120.

When a splice is desired, the motor 464 may drive the pulley 460 tolower the bottom of the loop 120 to the sensor 474-3. In variousimplementations, once the bottom of the loop 120 reaches the sensor474-3, the motor 464 may drive the pulley 460 a predetermined furtheramount, to lower the bottom of the loop 120 a predetermined distancebelow the sensor 474-3.

Alternatively, for splicing, the motor 464 may drive the pulley 460until a trailing end of the weight material is located at apredetermined location (such as the middle) of the splicing apparatus450. However, even if the trailing end has not yet reached thepredetermined location of the splicing apparatus 450, the motor 464 mayhalt movement of the pulley 460 once the bottom of the loop 120 reachesthe sensor 474-3, or at a predetermined distance thereafter. Once thebottom of the loop rises above the sensor 474-3, the motor 464 may onceagain actuate the pulley 460 to attempt to bring the trailing end of theweight material to the predetermined location of the splicing apparatus450. Once splicing is complete, the motor 464 may resume controlling thebottom of the loop 120 to be between the sensors 474-1 and 474-2.

The motor 430 drives the first and second axles 420 and 422 in order toprovide slack material from the spool 110. In this way, the frictionalforce required between the weight material and the pulley 460 isreduced. The spool 110 may be installed in such a way that a bottom loop480 is created below the spool 110. A dancer switch 484 detects theheight of the bottom loop 480.

The dancer switch 484 includes a rod 488 arranged in a directionperpendicular to the plane of FIG. 4D. The rod rides along the inside ofthe bottom loop 480. The dancer switch 484 pivots about a pivot point490. As the bottom loop 480 moves up, indicating less slack isavailable, the dancer switch 484 pivots about the pivot point 490. Asensor 494 across the pivot point 490 from the rod 488 detects thiscondition and instructs the motor 430 to rotate the first and secondaxles 420 and 422 to provide more slack material.

Referring now to FIG. 5, an isometric view of an exemplaryimplementation of the splicing apparatus 450 is presented. First andsecond clamps 502 and 504 are mounted to a base plate 508. The firstclamp 502 clamps the trailing end of the old weight material between afirst shoe 510 and the base plate 508. The second clamp 504 clamps theleading end of the new roll of weight material between a second shoe 512and the base plate 508. Adhesive tape (and, optionally, splice indicia,such as reflective tape) may be applied manually by an operator or by amechanical apparatus. Once the splice has been accomplished, the firstand second clamps 502 and 504 are released.

Referring now to FIG. 6, an isometric view of a spool lift 600 accordingto the principles of the present disclosure is presented. For exampleonly, weight material may arrive in heavy spools, such as 200 pound or250 pound spools. Multiple spools may arrive on a single pallet. Thepallet may be stored close to the dispensing apparatus 104.Alternatively, the pallet may be stored remote from the dispensingapparatus 104. In such circumstances, one or more spools may beseparately placed next to the dispensing apparatus 104.

The spool lift 600 includes a lifting head 604 that travels up and downa support beam 608. The lifting head 604 may be moved up and down thesupport beam by way of a manual crank 610. Alternatively, the liftinghead 604 may be raised and/or lowered by an electric motor. The supportbeam 608 attaches to a base 612, which includes rear casters 616 and618. The base 612 also includes front rollers 620 and 622. In variousimplementations, the spool lift 600 may be based on an MH-40 RollRunnerSeries Material Handling Cart from AzTech Machinery.

The lifting head 604 may be lowered along the support beam 608 until alower mechanical hard stop (not shown) is reached. An arbor 626 projectsfrom the lifting head 604. The lower mechanical hard stop may positionthe arbor 626 at the same height as the bore of the spool when the spoolis sitting on the pallet. The arbor 626 is inserted into the bore of aspool of weight material.

The spool lift 600 is moved toward the spool until a stop ring 628 atthe base of the arbor 626 contacts the spool. The operator then raisesthe lifting head 604, lifting the spool from the pallet. The liftinghead 604 may be raised to an upper mechanical hard stop (not shown).

The spool lift 600 is then maneuvered to the dispensing apparatus 104.Guides (not shown) may be installed on the floor in front of thedispensing apparatus 104. The guides may force the rollers 620 and 622in alignment with the dispensing apparatus 104. The spool lift 600 maythen be moved toward the dispensing apparatus 104 until mechanical floorstops are reached. These mechanical floor stops are positioned so thatthe spool will be directly above the axles 420 and 422 of the dispensingapparatus 104.

At this point, the lifting head 604 can be lowered to the lowermechanical hard stop, thereby placing the weight of the spool onto theaxles 420 and 422. The height of the rollers may be set to hold thespool at the same height as the spool would be held by the pallet.Therefore, when the lifting head 604 reaches the lower mechanical stop,the spool is resting on the rollers, and the spool lift 600 can beremoved from the dispensing apparatus 104. As described above, materialfrom the new spool may then be spliced to the material from the previousspool.

In a more automated implementation, the spool lift 600 of FIG. 6 may bereplaced by a robotic spool lift. For operation in high temperatureenvironments, portions of the dispensing apparatus 104 or the cuttingapparatus 106 may be located in a temperature-controlled environment.For example only, circuitry present in the cutting apparatus 106 may becooled. In addition, in environments with high amounts of particulatematter in the air, portions of the dispensing apparatus 104 and thecutting apparatus 106 may be located in an isolated chamber that usesfiltered air.

The broad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent to the skilled practitioner upon astudy of the drawings, the specification, and the following claims.

What is claimed is:
 1. An apparatus comprising: a receiving module thatreceives a desired weight value to correct an imbalance of a wheel/tireassembly; a conversion module that converts the desired weight value toa corresponding first amount of a wheel weight material; first andsecond rollers that engage first and second opposing sides of the wheelweight material; a motor that drives the first roller according to thefirst amount; a forcing member that presses the second roller in a firstdirection that forms an angle with an axis of the first roller; animplement that selectively forms a mark on the wheel weight material;and a cutting head that is selectively actuated to separate the firstamount from the wheel weight material.
 2. The apparatus of claim 1wherein the motor directly drives the first roller.
 3. The apparatus ofclaim 2 wherein a drive shaft of the motor is collinear with an axle ofthe first roller.
 4. The apparatus of claim 1 wherein the receivingmodule receives the desired weight value from a balancing machine. 5.The apparatus of claim 1 wherein the first amount is expressed as alength.
 6. The apparatus of claim 1 wherein the wheel weight material isa continuous strip, and wherein a linear density of the wheel weightmaterial is approximately constant along the continuous strip.
 7. Theapparatus of claim 1 wherein the forcing member includes a spring. 8.The apparatus of claim 1 wherein the first direction is perpendicular tothe axis of the first roller.
 9. The apparatus of claim 1 wherein theimplement includes: a scribe implement that selectively forms a scribemark on the wheel weight material; and a scribe cylinder thatselectively brings the scribe implement into contact with the wheelweight material.
 10. The apparatus of claim 9 wherein the scribecylinder is actuated in response to the motor having driven the firstroller for an angular distance corresponding to half of the firstamount.
 11. The apparatus of claim 1 wherein the cutting head isactuated in response to the motor having driven the first roller for anangular distance corresponding to the first amount.
 12. The apparatus ofclaim 1 wherein the conversion module selects a linear density based ona cross-sectional profile of the wheel weight material and converts thedesired weight value to the first amount based on the linear density.13. A method of balancing a wheel/tire assembly using the apparatus ofclaim 1, the method comprising: receiving the desired weight value forbalancing the wheel/tire assembly; converting the desired weight valueto the first amount of a wheel weight material; driving the first rolleraccording to the first amount; pressing the second roller in the firstdirection; selectively forming the mark on the wheel weight material;and selectively actuating the cutting head to separate the first amountfrom the wheel weight material.
 14. The method of claim 13 wherein thedriving includes directly driving the first roller with the motor. 15.The method of claim 14 wherein the first direction is perpendicular tothe axis of the first roller.
 16. The method of claim 13 furthercomprising receiving the desired weight value from a balancing machine.17. The method of claim 13 wherein the first amount is expressed as alength.
 18. The method of claim 13 wherein the wheel weight material isa continuous strip, and wherein a linear density of the wheel weightmaterial is approximately constant along the continuous strip.
 19. Themethod of claim 18 further comprising (i) determining the linear densitybased on a cross-sectional profile of the wheel weight material and (ii)converting the desired weight value to the first amount based on thelinear density.
 20. The method of claim 13 wherein the forming includespressing a scribe implement into contact with the wheel weight material.21. The method of claim 20 further comprising pressing the scribeimplement in response to having driven the first roller for an angulardistance corresponding to half of the first amount.
 22. The method ofclaim 13 further comprising actuating the cutting head in response tohaving driven the first roller for an angular distance corresponding tothe first amount.